1. Field of the Invention
The invention relates to a rip fence for use with a table saw and, in particular, to a rip fence having a locking device for locking the rip fence in an inoperative position.
2. Description of Related Art
Table saw is a woodworking tool consisting of a circular saw blade, mounted on an arbor which is driven by an electric motor. The blade protrudes through the surface of a table, which provides support for the material (e.g., wood) being cut.
U.S. Pat. No. 9,095,989 entitled “Rip fence with locking mechanisms” discloses a table saw having a movable rip fence, the table saw comprising a base including an upper cutting surface through which a blade extends; a front rail and a rear rail disposed on a front edge and a rear edge of the upper cutting surface respectively; and an adjustment wheel mounted on a front surface of the base; wherein the rip fence comprises an elongated casing having a front end and a rear end; a front clamping mechanism connected to the front end of the casing and including a frame, a lever pivotably secured to the frame to be pivotal between a locked position and a released position, the lever having an internal cam member, a clamping member pivotably secured to the lever, the clamping member having a hook at an open end, a spring biased shaft, and a C-clip for retaining an inner end of the shaft in the frame; and a rear clamping mechanism connected to the rear end of the casing and including a frame, a lever pivotably secured to the frame to be pivotal between the locked position and the released position, and a clamping member pivotably secured to the lever, the clamping member having a hook at an open end; wherein for the front clamping mechanism in the released position of the rip fence, the shaft engages the cam member; and a pivotal movement of both the lever and the clamping member causes the cam member to push the shaft inward until an inner end of the shaft is stopped by the frame, the hook is secured to a bottom of the rear rail, the lever is about oriented downward, the shaft is pushed outward to urge against the cam member, and the shaft is disengaged from the frame at the end of the pivotal movement; and wherein for the rear clamping mechanism a pivotal movement of both the lever and the clamping member from the released position of the rip fence causes the hook to secure to a bottom of the rear rail and causes the lever to be oriented about downward, thereby locking the rear clamping mechanism.
On drawback of the patent is that lever 42 of clamping mechanism 40 and lever 62 of clamping mechanism 60 are projected out of front and rear ends of the fence 20 and it may interfere with operation of the table saw.
Thus, the need for improvement still exists.